Comparative efficacy of a high or low dose of interferon alpha 2b in chronic hepatitis C: a randomized controlled trial.

ABSTRACT

OBJECTIVES: Our objective was to determine the relative efficacy of 6 months of treatment with 10 MU versus 3 MU of interferon-alpha 2b (IFN-alpha), three times weekly, in chronic hepatitis C (HCV) in a randomized trial. METHODS: Ten megaunits of IFN-alpha were given to 28 patients (group A), and 3 MU were given to 30 patients (group B). After treatment ended, follow-up was continued for 26 wk. RESULTS: Overall, the sustained response rate was higher in group A than in group B (16/26 or 61.5% vs. 12/28 or 42.9%, p = 0.17), but the difference did not reach statistical significance. However, it was higher in group A than in group B among patients with minimal or mild chronic hepatitis (15/20 or 75% vs. 9/24 or 37.5%, p = 0.013) and among those with mild or moderate fibrosis (15/17 or 88.2% vs. 11/19 or 57.9%, p = 0.042). IFN-alpha treatment significantly reduced histological activity index (HAI) scoring and all its parameters, except fibrosis, but the decrease was similar in the two groups. Sex, age, stage, and HCV genotype were statistically significant predictors of sustained response in univariate analysis. However, multiple logistic regression analysis revealed that advanced histological stage (severe fibrosis and cirrhosis) was the only significant prognostic factor of poor sustained response (RR = 31.0, 95% CI 2-460, p = 0.01), whereas the presence of genotype 1 had marginal statistical significance (RR = 5.0, 95% CI 0.9-28, p = 0.07). CONCLUSIONS: 1) A larger dose of IFN-alpha does not improve the sustained response rate; however, it may be of benefit in early stages of chronic hepatitis C. 2) Pretreatment, histological stage, and possibly HCV genotype appear to be the main prognostic factors of sustained response.